package com.wushijia.java8.misc;

import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.IOException;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.util.List;
import java.util.stream.Collectors;
import java.util.stream.Stream;

/**
 * @author Benjamin Winterberg
 */
public class Files1 {

  public static void main(String[] args) throws IOException {
    testWalk();
    testFind();
    testList();
    testLines();
    testReader();
    testWriter();
    testReadWriteLines();
    testReaderLines();
  }

  private static void testReaderLines() throws IOException {
    Path path = Paths.get("res/nashorn1.js");
    try (BufferedReader reader = Files.newBufferedReader(path)) {
      long countPrints = reader
          .lines()
          .filter(line -> line.contains("print"))
          .count();
      System.out.println(countPrints);
    }
  }

  private static void testWriter() throws IOException {
    Path path = Paths.get("res/output.js");
    try (BufferedWriter writer = Files.newBufferedWriter(path)) {
      writer.write("print('Hello World');");
    }
  }

  private static void testReader() throws IOException {
    Path path = Paths.get("res/nashorn1.js");
    try (BufferedReader reader = Files.newBufferedReader(path)) {
      System.out.println(reader.readLine());
    }
  }

  private static void testWalk() throws IOException {
    Path start = Paths.get("");
    int maxDepth = 5;
    try (Stream<Path> stream = Files.walk(start, maxDepth)) {
      String joined = stream
          .map(String::valueOf)
          .filter(path -> path.endsWith(".js"))
          .collect(Collectors.joining("; "));
      System.out.println("walk(): " + joined);
    }
  }

  private static void testFind() throws IOException {
    Path start = Paths.get("");
    int maxDepth = 5;
    try (Stream<Path> stream = Files.find(start, maxDepth, (path, attr) ->
        String.valueOf(path).endsWith(".js"))) {
      String joined = stream
          .sorted()
          .map(String::valueOf)
          .collect(Collectors.joining("; "));
      System.out.println("find(): " + joined);
    }
  }

  private static void testList() throws IOException {
    try (Stream<Path> stream = Files.list(Paths.get(""))) {
      String joined = stream
          .map(String::valueOf)
          .filter(path -> !path.startsWith("."))
          .sorted()
          .collect(Collectors.joining("; "));
      System.out.println("list(): " + joined);
    }
  }

  private static void testLines() throws IOException {
    try (Stream<String> stream = Files.lines(Paths.get("res/nashorn1.js"))) {
      stream
          .filter(line -> line.contains("print"))
          .map(String::trim)
          .forEach(System.out::println);
    }
  }

  private static void testReadWriteLines() throws IOException {
    List<String> lines = Files.readAllLines(Paths.get("res/nashorn1.js"));
    lines.add("print('foobar');");
    Files.write(Paths.get("res", "nashorn1-modified.js"), lines);
  }
}
